Safety joints



SAFETY JOINTS 4 Sheets-Sheet 1 Filed Dec. 6, 1954 @L m im M .Mdm EA May 24, 1960 Filed Dec. 6, 1954 M. M. KINLEY ETAL SAFETY JOINTS 4 Sheets-Sheet 2 f 36 ff/".4

. L-Jf INVENTORS ATTORNEYS M. M. KINLEY ETAL 2,937,854

SAFETY JOINTS May 24, 1960 4 Sheets-Sheet 4 Filed DSG` 6, 1954 a//r m/mw M/HMZ Mm WZ @y/ d5 B SAFETY JOINTS Myron M. Kinley, Los Angeles, Calif., and John C. Kinley and Bernhard Knust, Houston, Tex.; said Myron M. Kinley and said Bernhard Knust assignors, by direct and mesne assignments, of one-half to said Myron M. Kinley and one-half to said John C. Kinley Filed Dec. 6, 1954, Ser. No. 473,274 6 Claims. (Cl. 255-28) This invention relates to new and useful improvements in safety joints.

An object of this invention is to provide a new and improved safety joint for use in a well pipe or the like, which is adapted to be operated from the surface of the well by a wire line or a similar exible support.

An important object of this invention is to provide a new and improved safety joint for well tubing or other pipe, wherein the safety joint has the same internal or bore diameter as the well tubing, whereby Well tools may be moved through the safety joint without obstruction by such safety joint; the safety joint being releasable by rotation whereby the movement of the well tools through the joint cannot inadvertently release said safety joint.

Another object of this invention is to provide a safety joint which is particularly suitable for connection in a well pipe or the like, wherein the safety joint is adapted to be released by a turning action, and wherein an actuating device is associated with the joint for applying such turning action by a series of rotary jarring impacts or otherwise to said safety joint to eliect a release thereof so that the portion of the pipe above the safety joint can be retrieved from the well by lifting upwardly on the pipe.

A further object of this invention is to provide a safety joint for connection in a pipe string so as to permit a retrieving of the portion of the pipe string above the safety joint in the event that the portion of the pipe string below the safety joint becomes stuck in the well bore, such safety joint being releasable by the application of a rotary movement thereto with a release tool, the safety joint and the tool having means therewith to indicate to the operator of the release tool when the safety joint has been released by the rotary movement.

The construction designed to carry out the invention will be hereinafter described together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

Figure 1 is a view, partly in elevation and partly in section, illustrating an actuating tool for effecting the release of the safety joint of this invention.

Figure 2 is a sectional view illustrating in detail the safety joint of this invention in its normal locked position.

Figure 3 is a view similar to Figure 2, but illustrating the safety joint with the lock member in a released position, but prior to the separation of the parts of the safety joint.

Figure 4 is a view, partly in elevation, and partly in section, illustrating the safety joint of Figures 2 and 3 after it has been separated or released.

Figure 5 is a horizontal sectional view taken on line 5--5 of Figure 3.

tent O Figure 6 is a sectional view illustrating one modification of the safety joint illustrated in Figures 2-4.

Figure 7 is a sectional view illustrating anothermodilication of the safety joint of this invention.

Figure 8 is a sectional view taken on line 8-8 of Figure 4 and illustrates the indicator grooves in particular.

Figure 9 is a horizontal sectional view taken on line 9 9 of Figure 6.

Figure I() is an elevation illustrating a portion of the intermediate member as taken on lines 10`10 of Figure 7.

Figure 1l is a view, partly in Velevation and partly in section, illustrating a modified release tool for releasing the safety joint of this invention.

In the drawings, the letter S designates generally the event that the lower portion of the pipe P becomes stuck in a well bore or similar hole. As will be explained in detail, the safety joint S is so constructed that it has substantially the same internal diameter or bore as the rest of the pipe P so that under normal circumstances with the safety joint S connected, the safety joint does not interfere with the movement of well tools therethrough. The safety joint S is adapted to be released by a rotation of a portion thereof and therefore the longitudinal movement of well tools through the safety joint S cannot inadvertently release the safety joint. For effecting the release of the safety joint S, an actuating or release device A (Figure 1) of any suitable type for imparting rotary or turning movement to the safety joint S to rotate same is provided. Such actuating or release tool A is adapted to be lowered into the well pipe P on a wire line or other support (not shown) and is adapted to be operated by manipulation of the Wire line or other support from the surfaceofthe well to effect the turning movement for the release of the safety joint S.

The details of, one form of the safety joint S are shown in Figures 2-5, wherein an outer tubular member 10 has its lower externally threaded end 10a connected to a collar 12 on the lower portion `of the tubing or well pipe P. An intermediate tubular member 14 lits within the bore Itlb of the outer member 10 and the upper end 14a of such intermediate member 14 is threaded to the lower end of the upper portion of the well pipe P which extends to the surface of the well. Within the bore 14b of the intermediatemember 14, there is positioned an inner tubular member or lock sleeve 15 which is rotatable relative to the intermediate member 14, but is normally held against inadvertent rotation by one or more shear pins 17.

The lower portion of the outer member 10 has an inwardly extending annular shoulder 20 formed thereinfor supporting the lower ends of the intermediate member 14 and the inner member 15. Thus, downward movement of the intermediate member 14 and the inner mem-l ber 15 relative to the outer member 10y .is prevented.

The upward movement of the inner member 15 relative to the intermediate member 14 and the outer member 10 is limited by an annular inwardly extending shoulder 22 formed within the bore 14b of the intermediate member 14. The upper end of the inner member 15 contacts such annular shoulder 22, so that the inner rotatable member 15 is definitely coniined between the shoulders 20 and 22. In order to maintain'the intermediate member 14 lxed relative to the outer member 10 under normal conditions, the intermediate member 14 is formed witha plurality of lateral openings 24, each of which has a later ally slidable lug or latch member 25 therein.

Each lug 25 normally extends into a suitable recess 26 formed in the interior or inner wall of the outer member 10, such recesses 26 being provided in threaded inserts 27 which are mounted in the outer housing or member 10. The lugs 25 are held in their extended position within the recesses 26 by the contact of the inner or rear side 25a of each lug 25 with the external surface 15a of the inner rotatable member 15 (Figure 2). It will be evident that when the lugs 25 are thus held in their extended position, the outer member and the intermediate member 14 cannot be separated or moved with respect to each other. It should also be pointed out that the walls of the openings 24 are inclined or tapered and likewise the outer surface of the lugs 25 are similarly inclined or tapered so as to facilitate the inward movement of the lugs 25 relative to the intermediate member 14 after the lock sleeve has been moved to its release position (Figure 3), as will be explained. Each lug 25 is preferably provided with a groove b in the external surface thereof which permits uid to enter each recess 26 so as to minimize the possibility of forming a vacuum in such recess 26 upon retraction of the lugs 25 therefrom. Of course, other suitable means can be provided to accomplish the same result.

The inner member or lock sleeve 15 is provided with recesses 30 (Figure 3) in its external surface, with one recess 30 being provided for each of the latch lugs 25. The recesses 30 are circumferentially spaced so as to all be aligned with the matching lugs 25 upon a rotation of the inner member 15. When the lugs 25 are aligned with the recesses 30 (Figures 3 and 5), the lugs 25 can then move into the recesses 30; therefore, it will be evident that the recesses 30 are of a slightly larger size than the rear portion of the lugs 25. Each recess 30 preferably has an opening or port 31 associated therewith so as to facilitate the seating of the lugs 25 in the recesses 30. The openings or ports 31 are of a reduced size as compared to the recesses 30 and are suliciently small to prevent the lugs 25 from passing therethrough, but they do permit the displacement of iiuid as the lugs 25 move inwardly, so that the danger of forming a vacuum in the recesses 30 is diminished.

The inner rotatable member 15 has a pair of diametrically opposed longitudinal slots 15b which have upwardly curved walls 15e which converge into diametrically opposed pointed upper ends 15d. The walls 15C serve as a guide or cam surface for guiding the actuating tool into the slots 15b, as will be evident hereinafter. A longitudinal slot 32 is formed in the inner wall of the inner member 15 for each of the longitudinal slots 15b, whereby the recesses 32 form a continuation of the slots 15b with a shoulder 32a at the upper end of each recess 32 presenting a knife-edge. The longitudinal recesses 32 extend downwardly to the lower end of the inner member 15 and they are adapted to be aligned with longitudinal grooves 34 formed in the inner wall of the outer member 10 and extending through the lateral shoulder 20. The purpose of such construction will be evident hereinafter, but generally speaking, such construction permits the actuating tool A to move downwardly below the inner member 15 after same has been rotated to the released position, thereby giving the operator at the surface of the well an indication that the release position of the inner member 15 has been obtained.

The outer housing 10 is provided with a plurality of annular shoulders 35 which are suitable for connection to a iishing tool to effect the removal of the lower portion of the stuck pipe P after the safety joint has been disconnected and separated. Annular seal rings 36 are provided for forming a fluid-tight seal between the outer member 10 and the intermediate member 14.

For turning the inner lock member 15 to position the recesses 30 opposite the lugs 25, the release tool A (Figure 1) is provided which has ya rod 38 positioned within a sleeve 37 so that the rod 38 and the sleeve 37 are longitudinally movable relative to each other, with such longitudinal relative movement being controlled by the movement of a pin 39 which extends outwardly from the rod 38 into a shaped guide slot 40 in the sleeve 37. The lower portion 40a of the slot 40 is vertical or substantially vertical and the slot 40 gradually increases in inclination as it progresses upwardly so that the upper portion 40h of the slot 40 is substantially lateral or horizontal. Such construction of the slot 40 results in the rotational movement of the sleeve 37 relative to the rod 38 as the sleeve 37 is permitted to fall'by gravity from an extended position to the fully telescoped position shown in Figure l. Thus, the sleeve 37 would be in the fully extended position when the pin 39 is at the lower end of tl e slot 40 and it is in the fully collapsed or telescoped position (Figure 1) when the pin 39 is at or near the upper end of the slot 40. It should be noted that although the lower portion 40a of the slot 40 is illustrated as vertical, it is generally preferable to provide such lower portion 40a with a slight incline from vertical so that there is no sharp change in the movement of the pin 39 in the slot 40 as the sleeve 37 is dropped. The lower end of the rod 38 is threaded or otherwise suitably secured to a body 41 and such rod 38 is preferably prevented from rotating relative to the body 41 by a retaining set screw 45. The body 41 has at its upper end one or more substantially vertical or longitudinal anvil surfaces 41a which are adapted to be contacted by corresponding substantially vertical or longitudinal hammer surfaces 37a on the lower end of the sleeve 37. The hammer surface 37a is adapted to contact the anvil surface 41a when the sleeve 37 reaches its lower limit of travel to impart the rotary movement of the sleeve 37 to the body 41 with a rotary jarring impact. Preferably such surfaces 37a and 41a are slightly inclined with respect to vertical as indicated in the drawings, but for practical purposes they may be described as being substantially vertical or longitudinal.

The body 41 is formed with the longitudinal slot or opening 41b therethrough for the reception of a pair of latching arms 42 which are pivoted or hinged together at pivot pin 43. The latching arms 42 are constantly urged radially outwardly into engagement with the inner surface of the well pipe P by the spring 42 or other equivalent resilient means. If desired, the latching arms 42 may be retained or locked by any suitable mechanism during the lowering thereof into the well pipe for the actuation of the safety joint S. For example, such a locking mechanism is disclosed in the copending U.S. patent application of Myron M. Kinley, Serial No. 436,647.

For the purposes of this invention, various types of actuating or release tools may be employed so long as they are capable of rotating the inner sleeve 15 to release the safety joint S by a manipulation from the surface of the well. Preferably', of course, the actuating device is operable by the manipulation of a wire line or other similar flexible support. One example of another release tool A is illustrated in Figure l1, wherein the latch arms 142 are pivotally mounted at pivot pin 143 to the body 141, with a suitable longitudinal recess 141b being provided for the pivotal movement of the arms 142. A spring 144 urges the latch arms 142 outwardly. The body 141 is connected to a sucker rod 75 which extends to the surface of the well for rotation or turning by pipe tongs or any similar conventional equipment. Pipe could be substituted for the sucker rod 75, if desired. The upper ends 142a of each arm 142 serve as a trip or release lever for releasing the engagement of the arms 142 with the safety joint after the lock sleeve 15 has been turned to the release position, as will be explained in detail hereinafter.

In the operation or use of the safety joint of this invention, the safety joint S is positioned in the well pipe P at any desired point and normally would remain in the locked position shown in Figure 2, wherein the safety joint is locked so that the portions of the well pipe P above the safety joint S and therebelow remain firmly connected.v In the event that the well pipe becomes stuck in a well bore or hole, or for some other reason it becomes desirable to disconnect the portions of the well pipe P which are joined by the safety joint S, then the actuating tool A is lowered through the pipe P until the latching arms 42 on the actuating tool A engage the guide or cam surfaces e of the inner rotatable member 15. It will be noted that the latching arms 42 expand outwardly as they enter the upper portion of the bore 14h since such bore 14b is of an enlarged diameter as compared to the diameter of the pipe P. Such expansion of the arms 42 assures their contact with the cam surfaces 15C. Continued lowering of the actuating device A thereafter causes the arms 42 to be guided along the surfaces 15a into the longitudinal slots 15b and then downwardly into the longitudinal recesses 32. Because the shoulders 32a are knife edges, they do not interfere with the movement of the arms 42 into the recesses 32; The downward movement of the actuating tool A is stopped when the lower ends of the latching arms 42 hit the annular shoulder 20.

' When the arms 42 are rst positioned in the longitudinal recesses 32, the wire line or other flexible support for the sleeve 37 is still raised to hold the sleeve 37 raised with respect to the rod 38 and the body 41, so that the sleeve 37 is in its fully extendedposition with respect to the rod 3S. In such extended position, the pin 39 is at the lower end of the slot 40. As the sleeve 37 is permitted to fall by gravity relative to the rod 38, the engage ment of the pin 39 with the wall of the slot 40 causes the sleeve 37 to rotate relative to the rod 38, and with the slot 40 formed with an increasing inclination as it extends upwardly, the rotational force gradually increases as the sleeve 37 moves downwardly until the hammer surface 37a of the sleeve 37 finally hits the anvil surface 41a on the body 41 to thereby transmit a rotary jarring impact from the sleeve 37 to the body 41. Such impact is in turn transmitted to the inner sleeve or member 15 through the engagement of the latching arms 42 in the longitudinal slots 15b for initially shearing or severing the shear pin or pins 17.

After a series of successive raisings and lowerings of the sleeve 37 so as to impart a series of rotary jarring impacts to the inner member 15, the member 15 is moved or turned so as to position the recesses 30 in the member 15 in alignment with the lugs 25. The extent of turning in order to obtain such alignment is preferably about forty-five degrees (45), although it will be evident that other amounts could be used.

In order to prevent further rotation of the member 15 and thereby to prevent moving the recesses 30 out of alignment with the lugs 25, and also to give an indication to the operator that such alignment has been, obtained, the longitudinal recesses 32 are aligned with a pair of the grooves 34 so that the arms 42 no longer seat upon the lower shoulder or ange 20, but are free to drop through the grooves 34 (see dotted lines in Figure 3). When such dropping of the entire release tool A occurs, the increased weight of the tool will be indicated to the operator at the surface of the well and he can then retrieve the actuating tool A from the well pipe P.

The operator can also check to be certain that the tool is in release position before bringing his wire line equipment out of the hole by lowering the release tool through the grooves 34 again.

V Thereafter, the intermediate member 14 and the inner member 15 can be raised relative to the outer member 10 which latter has connection with the stuck portion of the well pipe P by simply raising upwardlyon the upper portion of the well pipe P. As the pipe P is thus pulled upwardly at the surface of the well, the slidable lugs 25 are forced inwardly into the recesses 30 by reason of the sliding coaction between the inclined or tapered internal surface 26a of the recess 26 and the inclined or tapered external surface 25a of the lugs 25. It will be evident that the lugs 25 are retained against outward displacement on the upward trip by reason of thetapered construction of the inner wall of the openings 25 (Figure 4). It should also be noted that with the construction of the safety joint of this invention, once the lugs 25 are aligned with recesses 30, the intermediate sleeve 14 can be rotated either to the right or left which moves the lugs 25 out of alignment with the openings 24. In some instances, such rotation assists in releasing the pipe should it be stuck above the safety joint S.

After the safety joint has been separated and the upper portion of the pipe P has been removed from the well,

then conventional shing tools can be lowered into the well and engaged with the fishing shoulders 35 to retrievey the lower portion of the well pipe P from the well bore.

It should be noted that Figures 2-4 illustrate the device with four of the indicating grooves 34. Such arrangement positions the grooves 34 at about ninety de-V grees with respect to each other so that the sleeve 15 can be turned in either direction (either clockwise or counterclockwise) and still the recesses 32 can be aligned vertically with a pair of the grooves 34 after the member 15 has moved only forty-five degrees (45). Thus, if the actuating tool were adapted to rotate the sleeve 15 in a counterclockwise direction instead of clock-V wise as used from the top of Figure 1 of the drawings, the opposite pair of grooves 34 would be utilized. l

In Figure 6, a modified form of the safety joint S of this invention is illustrated, wherein the parts which are identical with the parts in the rst form of the invention shown in Figures 1-5 have the same numerals. The outer member is substantially identical with the outer member 10, except that the inserts 27 are not utilized, but instead the recesses 126 are formed in the inner wall of the member 110. Also, additional recesses 50 of a reduced diameter as compared to the recesses 126 are formed in the member 110 for the reception Aof a coil spring 51 or a similar resilient means which extends into contact with the outer face or surface of the lug 25. The spring 51 for each lug 25 thus serves to urge the lug 25 inwardly so that when the inner member 115 has been rotated to align the recesses 30 with such lugs 25, the springs 51 act to move the lugs 25 laterally into the recesses 30, whereby they are completely retracted fromrthe recesses 126. The outer member 110 and the intermediate member 114 have interengaging splines 76 and 77, respectively, which provide a rugged interconnection. Also, the bottom of member 114 is held by vthe lugs 25 in contact with the annular shoulder 20 so that the pipe in which the 'safety joint is located can be used as drill pipe or other use wherein full strength for rotation or compression of the pipe is required without damaging the lugs 25. Also, in the Figure 6 modification, the longitudinal recesses 32 are eliminated whereby the latching arms 42 of the release device A do not drop or fall when the sleeve or inner member 115 has been rotated approximately forty-five degrees (45) to the position shown in Figure 6. Since the springs 51 urge the lugs 25 outwardly when the recesses 30 become aligned in the modification of Figure 6, there is practically no danger of moving the recesses 30 past the lugs 25 without effecting a retraction or inward movement of the lugs 25 to the release position. However, the slots 32 and the grooves 34 in shoulder 20 of Figure 2 could be utilized for a positive release of the arms 42 and indication thereof, if desired. Also, other types of positive release and indicator means for the release tool can be provided such as the diametrically opposed dogs 8b which are positioned in the bore of the intermediate member 114 and are so located with respect to the recesses 31 and the slots 15b that the release levers 142a of the tool A' contact the dogs 80 and are moved radially inwardly thereby when the recesses 30 arealigned with' the lugs 25. The inward. movement' of the levers 142a moves the latch arms 142 inwardly a sufiicient distance so that they fit within the bore ofthe lock sleeve 115 and are thus released from grooves b for falling by gravity through the sleeve 115. Thus, there is an indication to the operator at the surface of the well that the lugs 25 have been retracted into the recesses 30.

The operation of the form of the invention shown in Figure 6 is substantially identical with that described above in connection with Figures 2-5. An actuating or releasing device such as that shown in Figure l is lowered into the well pipe P so that the arms 42 extend into the longitudinal slots 15b. The rotary jarring impacts are applied to the actuated device A to the inner member 115 to rotate same to initially shear the shear pin 1'] and to ultimately move the recesses Si) into alignment with the lugs 25, whereupon the springs 51 urge the lugs 25 inwardly to retract same from the recesses 125. Then, the intermediate 114 and the inner member 115 can be released and moved upwardly with respect to the outer member 110 so that the safety joint S is then released.

A third modification of the safety joint S of this invention is shown in Figures 7 and l0, wherein identical parts, as compared to Figures 2-5, have the same numerals. The outer member or housing 210 is substantially identical with the outer member or housing 10, except that the inserts 27 are not employed, but instead the recesses 226 are formed in the inner wall of the member 210. Latching lugs 22S are formed in a cylindrical shape and are adapted to be positioned in the cylindrical recesses 226. A leaf spring 55 is provided for each lug 225, and each spring 55 has its upper end secured to the intermediate member 214 and its lower end is secured to one of the lugs 225, with the majority of each leaf spring 55 being free to move within the slot 57 formed in the intermediate member 214 so as to permit inward and outward movement of the lugs 225. The springs 55 tend to urge the lugs 225 inwardly, but the inner surfaces 22551 of the lugs 225 ordinarily are in contact with the external surface 215:1 of the inner member 215 so as to prevent such inward movement. However, when the inner member 215 is rotated through forty-five degrees (45) or some other predetermined distance, the lugs 225 are then aligned with openings 230 for permitting sufiicient inward movement of the lugs 225 to retract same from the recesses 226.

The rotation of the inner member 215 is obtained in the same manner as the rotation of the member 15 in Figures 25, namely, by a lowering of the actuating or release device A so that the arms 42 interfit with the longitudinal slots 15b and thereafter the rotary jarring impacts are applied to the inner member 215 to rotate same. Once the member 215 has been rotated sufficiently to align the openings 23) with their respective lugs 225, the springs 55 hold the lugs 226 in the retracted position out of the recesses 226; therefore, no means is utilized to indicate to the operator at the surface of the well that the device has been moved to the released position. However, it will be appreciated that an indicating means such as the grooves 34 shown in Figures 2-5 could be incorporated in the modification of Figures 7 and 8 or the modification of Figure 6, if desired.

It is believed evident that the latching lugs 225 could be tapered or inclined in the same manner as the lugs 25 of Figure 2, or, the tapered lugs 25 could be formed as cylindrical in the modification of Figure 6, rather than as illustrated. Also, it should be pointed out that the shear pins 17 are not essentiai, but could be eliminated since such pins 17 are merely a safety item to prevent premature rotation of the sleeve 15. However, in the usual case, the frictional Contact of the member 15 with the member 14 is sufficient to accomplish that purpose. In fact, it. is important that the sleeve 15 be in frictional formed by splines 76 and 77 (Figures 5, 6 and 9) could be used in any of the other forms of the safety joint. Also, the levers 142e of the release tool A could be provided on the tool A if it is desired to provide the release of the latch arms 142 by the coaction with the dogs 80 instead of by the grooves 34 in any of the various modifications.

It seems obvious that the movement of the sleeve 15 from the locked position of Figure 2 to the released position of Figure 3 could be a rotational movement combined with longitudinal movement instead of merely rotational movement as described above.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed is:

l. In a well tool operable by rotation of an inner member by actuating means, means to test the operation of said tool including, a driving member on said l actuating means for imparting rotation from the actuating means to said inner member, a first recess for said driving member in said inner member, a shoulder in said tool supporting said actuating tool during the rotation of said inner member, and a further recess in said shoulder adapted for alignment with said first recess to form a continuation thereof and to receive said driving member to enable said actuating means to fall by gravity out of said first recess into said further recess and to pass below said shoulder so that the actuating tool is not supported thereby when said inner member is in the proper position for operation of said well tool, whereby an indication is obtained at the surface of the well that the tool is in the proper position.

2. A safety joint for pipe, comprising a first tubular member connected to one section of the pipe, a second tubular member connected to another section of the pipe and mounted within said first tubular member for movement relative thereto, said first tubular member having a latching recess formed in its inner surface, a lug mounted in said second tubular member for movement relative to said second tubular member, lock means in the bore of said second tubular member to retain said lug in said recess to maintain said tubular members in a locked position, and means mounting said lock means for effecting a release of said lug from said recess upon a rotation of said lock means, said lock means including a sleeve having a recess therein into which said lug is movable for effecting the release of the connection between the tubular members, whereby upon movement of said members relative to each other, the safety joint is released.

3. A safety joint for pipe, comprising a first tubular member connected to one section of the pipe, a second tubular member connected to another section of the pipe and mounted within said lirst tubular member for movement relative thereto7 said first tubular member having a latching recess formed in its inner surface, a lug mounted in said second tubular member for movement relative to said second tubular member, lock means in the bore of said second tubular member to retain said lug in said recess to maintain said tubular members in a locked position, and means mounting said lock means for effecting a release of said lug from said recess upon a rotation of said lock means, said lock means including a sleeve having a recess therein into which said lug is` movable for eiecting the release of the connection between the tubular members, said sleeve having an internal bore of at least substantially the same size as the bore of said pipe, whereby well tools may be moved through the pipe without obstruction by the safety joint.

4. A safety joint for pipe, comprising a iirst tubular member connected to one section of the pipe, a second tubular member connected to another section of the pipe and mounted within said iirst tubular member for movement relative thereto, said first tubular member having a latching recess formed in its inner surface, a lug mounted in said second tubular member for movement relative to said second tubular member, lock means in the bore of said second tubular member to retain said lug in said recess to maintain said tubular members in a locked position, and means mounting said lock means for eiecting a release of said lug from said recess upon a rotation of said lock means, said lock means having a connection means therewith for engagement with an actuating device for imparting rotation from said actuating device to said lock means, and wherein said lock means also has guide means in addition to said connection means for automatically guiding said actuating device into the means for engaging same. v

5. A safety joint for well pipe and the like, including an outer tubular member connected to the lower portion of the pipe, an intermediate tubular member disposed within said outer tubular member and having connection with the upper portion of said well pipe, an inner tubular member Within said intermediate member and mounted for rotation relative thereto, coacting latching means on said intermediate and outer members for preventing relative longitudinal and rotational movement therebetween, said inner tubular member locking said latching means against disengagement whereby said upper and lower portions of the Well pipe are normally connected together by the safety joint, and means on said inner tubular member for permitting a disengagement of said latching means upon a rotation of said inner tubular member relative to said intermediate tubular member, said inner tubular member having means therewith for engagement by an actuating device for imparting rotation from said actuating device to said inner tubular member,

and means for causing said actuating device to fall by gravity throughvsaid inner tubular member upon dis engagement of said lat-:hing means.

6. In combination with an actuating tool adapted to be suspended from and manipulated with a flexible wire line, a rst tubular member connected to one section of a pipe, a second tubular member connected to another section of the pipe, latch means to normally latch said tubular members together to thereby prevent separation of said sections of pipe, lock means to retain said latch means in the latched position, means mounting said lock means for rotation relative to said latch means for effecting a release of said latch means, and means to releasably connect said actuating tool tosaid lock means for imparting rotation from said actuating tool to said lock means upon manipulation of said actuating tool with said wire line to eifect the movement of said lock means for the release of said latch means, said latch means including, a recess in one of said tubular members and a laterally movable lug in the other of said members, said lock means retaining said lug in said recess, and a spring means urging said lug into contact with the external surface of said lock means, and means on said lock means adapted to be aligned with said lug upon rotation of said lock means whereby said spring urges said lug thereinto for eiecting a disengagement of said lug from said outer tubular member.

References Cited in the tile of this patent UNITED STATES PATENTS 998,531 Ketelsen July 18, 1911 1,450,024 Edwards May 27, 1923 1,589,781 Anderson June 22, 1926 1,796,611 Montgomery Mar. 17, 1931 1,824,257 Bull Sept. 22, 1931 2,361,094 Hammer Oct. 24, 1944 2,373,648 Boynton Apr. 17, 1945 2,532,686 Ware Dec. 5, 1950 2,591,531 Fishback Apr. 1, 1952 2,739,654 Kinley et al Mar. 27, 1956 

